1. Field of the Invention
The present invention relates to the field of RF signal transmission, and more particularly to an RF switch device, a magnetic resonance imaging system and an RF signal transmission method.
2. Description of the Prior Art
As shown in FIG. 1, in the magnetic resonance imaging system, the receiver coil receives the RF signals emitted from the human body, and the received signals are connected to the system plug via the coil plug of the receiver coil. The system plug is connected with the receiver coil channel selector via the long RF cable, and the receiver coil channel selector chooses the 16-channel RF signals suitable for the imaging device from the inputted RF signals to feed to the imaging device to form the corresponding images from processing of the RF signals.
In order to achieve better signal noise ratio, most of the existing receiver coils are arranged in a coil array, and therefore each receiver coil includes multiple units. Moreover, to meet the needs of clinic application, the magnetic resonance imaging system allows for connection of multiple coils simultaneously. To achieve this, it is necessary to provide a large number of corresponding RF channels.
Taking the structure shown in FIG. 1 as an example, the magnetic resonance imaging system provides 4 system plugs of 8-channel RF signals, so that up to 32 channels of RF signals can be fed to the receiver coil channel selector, and then the 16-channel RF signals are outputted to the imaging device after being selected by the receiver coil channel selector. As shown in FIG. 1, the complexity of the receiver coil channel selector is 32×16, which is very complicated. In addition, an expensive 32-channel long RF cable is needed to connect the system plug to the receiver coil channel selector. Obviously, such a structure not only makes the circuits of the system very complicated, but also leads to a very high cost.
Normally, since both the system plug and coil plug are of a fixed design, the coil 3 containing the 6-channel RF signals and the coil 4 containing the 2-channel RF signals as shown in FIG. 1 cannot be simultaneously connected to either system plug 3 or system plug 4, but can be only separately connected to the plug 3 and plug 4. As a result, 8 RF channels in the plug 3 and plug 4 are idle. In this case, 8 RF channels in the long 32-channel RF cable are also idle, causing huge waste.